We have new data which shows that the 25th October spike wasn’t part of the gradual Penguin 3 roll-out. It appears the update had a lot to do with on-page factors and is (among other things) related to how Google treats thin content pages and soft 404s.

Specific Cases

We checked a number of other web properties to make sure this wasn’t a coincidental date match. There were several instances of an increase in soft 404 pages all on, or around the 25th October:

After inspecting each case of newly flagged soft 404s we found several instances of correctly classified pages which failed to returned 200 instead of 404. There were also a number of interesting borderline cases, most with the detection date correlating to the recent update.

Example 2: Low Value Page

Example 3: Tag Pages

In this example I can share full details as the site in question is an old pet project. Essentially we’re talking about a classic, tag pages containing the “trigger” type of statement in the content area:

Example 4: Zero Result Pages

This one is the case of a zero result search, more specifically an indexable zero post author page in WordPress. The page was first detected on the 25th October alongside a couple of tag pages similar to our previous case with analogik.com.

Dan Petrovic, the managing director of DEJAN, is Australia’s best-known name in the field of search engine optimisation. Dan is a web author, innovator and a highly regarded search industry event speaker.